There is an interesting post at http://knuckledraggin.com/2017/07/logging-and-transport-merced-river-canyon-yosemite/ of logging operations in the Yosemite, California, area. That post features silent movies (probably taken with 8mm film cameras back in the day). But lots of interesting stuff, mostly flatcars with logs being raised or lowered by cables. Also shows employees attaching cables to the cars. Anyone who is building a model RR dealing with logging railroads will especially benefit.